Window jack



ay 3, 1933; 11... A. DUNCAN 5 WINDOW JACK Filed Aug. 12, 1935 FIGQ4 7 I v INVENTOR.

Patented May 3, 1938 UNITED STATES PATENT GFFHCE 3 Claims.

The invention relates to improvements in window jacks (a device used to form a platform to stand on while on the outside of the upper floor windows) in which a screw type clamp gives a viselike grip to the window sill for anchorage, and the objects of the improvements are: first, to provide quick adjustment of the window jack to fit different widths of window sills; and second, to afford positive and accurate anchorage of the window jack to the window.

One form of the invention is illustrated in the accompanying drawing, in which Fig. 1 is a side view of the entire device and Fig. 2 a detail view of thread bar sill clamp assemblage, Fig. 3 is a top View of Fig. 1 using the bar anchorage and Fig. 4 is a transverse sectional view of the combination sill clamp on the line 4-4 of Fig. 3.

The platform l constitutes the frame work of the device, the legs 2--2, and leg braces 3-3 2 are free jointed and can be adjusted by having different places of union 4. Rails 5-5 offer the user added safety and are free jointed and can be folded down on the platform I when not in use.

25 The thread bar 6 is fitted in a slot I and is held therein by thrust washers 8-9 riveted to its ends, the ends passing through bearings IU-I I and journaled therein as shown in Fig. 2, said bearings being bolted I2 to platform I. The thrust washers 89 in cooperation with bearings ItlIi take care of the horizontal pull of the thread bar 6.

The thread bar 6 passes through a hole I3 in sill clamp I l and each is threaded to match, the thread bar 6 being of proper length as to offer a wide range of adjustment to sill clamp It. By turning crank it, sill clamp I4 is made to travel back or forth on thread bar 6, this in cooperation with legs 2?. constitutes the adjustable sill clamp anchorage.

Sill clamp I4 has a projection It extending below platform I which is the anchor. The flanges Il' extend over the edges of the slot I, on the bottom and top side of platform I, thus bracing and guiding sill clamp M, thereby eliminating all vertical strain on the thread bar 6.

A hole I8 on the top of the sill clamp and at right angles with platform I is for the purpose of providing a bar anchorage. By passing a bar I9 through this hole an anchorage can be had across the window from casement to casement, the bar being held rigid by thumbscrew 20.

A pair of angle irons 2I reinforce and are held to the underside of platform I by bolts 22. The ends of these angle irons are flush with the edge of platform I and each end contains a bolt 23 that is welded thereto, the bolts 23 extending out from platform I suitable to anchor thereto legs 22, braces 33 and rails 5-5.

To anchor the window jack to the window Fig. 1, rails 5-5 are folded onto platform I to allow clearance out the window. Legs 22 contact the wall 24 outside and below the window, the place of contact 25 being had at the lowest point of legs 2-2. With platform I resting on the window sill 26, thread bar 6 is revolved by turning crank I5 which propels sill clamp M toward and contacts sill 26, the point of contact being had by projection Hi. It is intended to turn the crank until pressure is placed on the points of anchorage.

Fig. 3 is a top View of the window jack with the bar anchor It in place. The window jack is placed in the same position for a bar anchorage as shown in Fig. 1. A bar it is placed an equal distance through the hole it with ends overlapping the casement. By turning the crank I5, thread bar 6 is caused to revolve, this in turn propels sill clamp I l toward the window and contact is made to the easements by the ends of the bar at points 21!. This in cooperation with legs 2-2 constitute the bar anchorage. Bar anchorage is intended for use on those windows where the sills do not allow an adequate sill anchorage.

The anchor projection It has an angle toward the sill 2t and legs 2-2 have a slight angle toward wall 24. With the window jack anchored to the window Fig. 1, any added weight placed on platform I over legs 2-2 will cause the window jack to wedge or bind and adhere more firmly to the window, due to the angles of legs 2--2 and projection I6.

To remove the window jack from the window, rails 5-5 are folded onto platform l. By raising the outside end the whole device is loosened and can then be removed. For the sill or bar anchorage no adjustments need be made from window to window of equal widths.

What I claim is:

1. A window jack comprising a frame, a threaded bolt journaled in said frame, a clamping member provided with a threaded bore adapted to receive said bolt, said bolt adapted to be revolved to move said clamping member longitudinally of said frame, said clamping member being provided with a downwardly extending flange to engage a window sill and a cross bar to engage the opposite sides of the casement.

2. A device of the class described comprising a frame adapted to rest upon a window sill, a threaded bolt journaled in said frame, a clamp provided with a threaded opening to engage said bolt, corresponding horizontal recesses in said clamp forming guides, said clamp being provided with a flange adapted to engage a window sill, and a bar carried by said clamp and adapted to engage the corresponding vertical portions of the window frame.

3. A window jack comprising in combination with a frame adapted to rest on a window-sill,

an adjustable clamping member mounted to move longitudinally in said frame, said clamping memher being provided with openings arranged at right angles to each other, operating means for said clamping member engaging one of said openings, a transverse anchoring member mounted in the other opening, and a downwardly extending flange formed integral with the clamping member and adapted to engage a window-sill.

LOMAN ADOLPH DUNCAN. 

